Production of polycyclic hydrocarbons



March 2, 1948. w. .1. MAT-rox 2,436,932

PRODUCTION OF POLYCYCLIC HYDROCARBONS Filed April 25, 1945 Zarza Patented Mar. 2, 1948 UNITED 4STAT PRODUCTION F POLYCYCLIC HYDROCABBONS William J. Mattox, La Grange; Ill., assignor to Universal Cil Products Company, Chicago, Ill.. a corporation of Delaware Application April z5, 194s. serial No. 590,213

(ol. aso-ssa) 4 Claims. l

This application is a continuation-in-part of my abandoned copending application Serial No. 496,450, led July 28, 1943;

This invention relates to a process for :manufacturing a polycyclic aromatic hydrocarbon and more particularly for manufacturing naphthalene.

An object of this invention is to produce a naphthalene hydrocarbon.

A further object of this invention is to treat ethylene, and benzene or ethylbenzene at a conversion temperature in the presence of a synthetically prepared silica base catalyst.

One speciiic embodiment of the present invention relates to a process for producing naphthalene which comprises reacting benzene and ethylene at a temperature of from about 525 to about 700 C. in the presence of a synthetically prepared catalyst comprising silica and a member selected from the group consisting of alumina, thoria, and zirconia. v

A further embodiment of this invention relates to a process for producing naphthalene which comprises reacting an ethylbenzene at a temperature of from about 525 to about 700 C. in the presence of a syntheticaliy prepared catalyst comprising silica and a member selected from the group consisting of alumina, thoria, and zirconia.

Suitable charging stocks for my process comprise a benzene hydrocarbon capable of forming a more-highly ethyiated benzene hydrocarbon in the process. 'Ihese charging stocks include benzene and ethylene, an ethylbenzene and ethylene, and an ethylbenzene, or hydrocarbon fractions containing these hydrocarbons. The preferred ethylbenzenes are mono-ethylbenzene and orthodiethylbenzene. When an ethylbenzene is employed it may be charged to the process from an outside source or it may be formed in the process by interaction of benzene and ethylene.

Catalysts utilizable in my process for producing naphthalene hydrocarbons comprise composites of synthetically prepared silica and an oxide selected from the group consisting of aluminum oxide, thorium oxide, and zirconium oxide.

These catalytic materials may be utilized in the form of powder, granules, or shaped particles, such as pellets or spheres, the latter formed by suitable pelleting or other shaping operations. In producing naphthalene, a` hydrocarbon charging stock as mentioned above is contacted with the catalyst at a temperature of from about 525 to about 700 C. and at a pressure of from subatmospheric to about 30 atmospheres. The benzene hydrocarbon such as ethyibenzene which is treated in my process is charged at a rate corresponding to an hourly liquid space velocity of from about 0.1 to about 3.0. f

When employing catalysts in the form of solid particles they may be utilized in the form of xed masses or they may be contacted with the reactant material in the so-called iluidized or moving bed types of processes.

In order that the invention may be more clearly understood, reference is made to the accompanying diagrammatic drawing which illustrates the process of my invention in one of its more specific modications.

As indicated in the drawing, benzene is introduced through line i, is commingled with ethylene in line 2, and then directed into conversion zone 3. In this conversion zone, the reaction mixture is contacted with a suitable catalyst, such as heretofore mentioned, under controlled conditions o! temperature, pressure, and reaction time. The reaction products which comprise naphthalene, ethylbenzene, and unconverted benzene and ethylene are directd through line 4 to separation zone 5. From separation zone 5, any unconverted ethylene and benzene are removed and returned by means of line 6 to the conversion zone. Also ethylbenzene formed in the process and not converted into naphthalene may be recycled through lines 6, I, and 2 to further treatment in zone 3. A

If desired, additional ethylene and ethylbenzene may be added to the recycle stream of ethylbenene in order to form diethylbenzene which may be subjected to dehydrocyclization to form additional naphthalene. The reaction product containing naphthalene is removed from separation zone 5 through line 'l and is directed to purication zone 8 wherein it may be subjected to steam distillation and/or sublimation, or to other suitable means of purification to yield a puriiied naphthalene fraction which is removed through line 9 to storage.

The following examples are included to illustrate the operation of my process although they are not to be construed to limit unduly the broad scope of the invention.

Example I Equimolecular proportions of benzene and ethylene are passed at atmospheric pressure through a reactor containing a silica-alumina catalyst maintained at a temperature of 550 C. When the benzene is charged at an average hourly liquid space velocity of 0.2, the yield of naphgaseosa thaleneiswbaseduponthewcightotthe benaenechargcdtotheptoocss.

ample 1r liiihylbenaenewasreaciiedintheprelanoetotl 5 a silica-alumina catalyst at a temperature oi 550 C..v atmospheric pressure, and at an ethylbenzene-charging rate corresponding to an hourcomprises reacting a charging stock comprising essentially mono-ethylbenzene at a temperature of from about 525 to about 100 C. and a liquid hourly `space velocity o1 from about 0.1 to about 3.0 in the presence of a synthetically prepared catalyst comprising silica and at least one metal oxide selected from the group consisting of alumina, vthoria., and zirconia.

2. The process deilned in claim 1 further char- 4 l acteriled in that the catalyst comprises a synthetically prepared composite o! silica and alu- 3. The process deiined in claim 1 further char-A acterixed in that the catalyst comprises-a synthetically prepared composite oi' silica and zirconia 4. ''he process defined in claim 1 further characterized in that the catalyst comprises a syn- 19 thetically prepared composite of silica, alumina.

and zirconia.

WILLIAM J. MA'IIOX.

REFERENCES CITED The following references are ot record in the ille oi.' this patent:

UNITED STATES PATENTS. I

Number Name Date go 2,110,833 Mark et al Mar. 8, 1938 2.360.358 Mattox Oct. 17, 1944 2,389,445 Matto! et al. Nov. 20, 1945 Schulze et al. Feb. 19, 1946 OTHER REFERENCES Thomas et al., J. A. C. 8. 86, 1694-6. 

